Waste paper stock pump



May 28, 1940.

F. R. FORREST WASTE PAPER STOCK PUMP Filed Feb. 23, 1938 2 Sheets-Sheet1 y 1940. F. R. FORREST 2,202,790

WASTE PAPER STOCK PUMP Filed Feb. 23, 1958 2 Sheets-Sheet 2 l atentedMay 28, 1946 UNITED STATES PATENT OFFICE WASTE PAPER STOCK PUMPApplication February 23, 1938, Serial No. 191,879 12 Claims. (01.103-115) This invention relates in general to improvements in hydraulicmachines and more particularly to rotary machines adapted to conduct,without clogging, a flow of fluid containing filamentary material. Theinvention is more specifically applicable to hydraulic pumps of the typedisclosed and claimed. in U. S. Patent No. 1,763,595, F. H. Paatsch,June 10, 1930.

Hydraulic machines of the centrifugal or axial type are frequentlyutilized to propel a flow of fluid containing filamentary material or tobe actuated thereby, but in either case it is necessary to insure thatfilamentary material may not enter the clearance space between therunner and the casing of the machine to avoid clogging the space betweenthe runner and the casing. The prevention of clogging is generallyobtained by utilizing a runner or impeller of the so-called closed typehaving machined surfaces cooperating with wearing rings in the casing tosubstantially seal the clearance between the runner and the suction sideplate of the casing, and by flushing the clearance with a flow of fluidfree from clogging material. It is, however, not possible to use arunnerof the closed type when the addition of clearance flushing fluid to thefluid passing through the machine is objectionable. For example, whenthe fluid is waste paper stock, the addition thereto of flushing waterthrough the pump clearance would thin the stock to an excessive extent.It is then necessary to use an impeller of the so-called open type andto provide means for preventing filamentary material such as string andrubber bands from penetrating into the clearance space between therunner and the casing. In particular, the stationary and movable vanesof the machine must be so shaped that filamentary material impingingthereon is returned into the fluid stream rather than being allowed todrift into the pump clearance. The invention is equally applicable tohydraulic turbines and to hydraulic pumps.

It is therefore one of the objects of the present invention to provide arotary hydraulic machine, either motor or pump, adapted to conduct,without clogging, a fluid stream containing filamentary material. IAnother object of the present invention is to provide a rotary hydraulicmachine adapted to conduct a fluid stream containing filamentarymaterial and which does not require any means for removing material fromthe clearance space between the machine casing and runner.

Another object of the present invention is to provide a rotary hydraulicmachine adapted to conduct a fluid stream containing filamentarymaterial in which filamentary material imping-' ing on a movable orstationary vane is returned into the fluid stream.

Another object of the present invention is to 5 provide a rotaryhydraulic machine adapted to conduct a fluid stream containingfilamentary material in which filamentary material impinging on thevanes of a runner is prevented from penetrating into the clearance spacebetween the runner and the casing.

Objects and advantages other than those above described will be apparentfrom the following description. when read in connection with theaccompanying drawings, in which:

Fig. l is a View partially in axial cross section through and partiallyin elevation of a centrifugal pump forming an embodiment of the presentinvention;

Fig. 2 is an end view of the runner of the pump illustrated in Fig. 1.

Fig. 3 is an enlarged fragmentary view in perspective of the inlet edgeof the runner illustrated in Figs. 1 and 2;

Fig. 4 is a fragmentary end View of a modified embodiment of the pumprunner;

Fig. 5 is a View in cross section taken on plane V-V in Fig. 4;

Fig. 6 is an axial cross section through a pump of the axial flow typeforming another embodiment of the present invention; and

Fig. 7 is a view in perspective of the runner of the pump illustrated inFig. 6.

Referring more particularly to the drawings by characters of reference,reference numeral ll designates a split casing forming a housing for anopen type runner or impeller 12 mounted for rotation therein. The runneris fastened on a shaft l3 supported in any suitable bearing (not shown)and connected with a suitable driving means (not shown). The shaftextends into the pump casing through a stuffing box containing a packingl4. Leakage of fluid from the pump casing through the stufling box isprevented by introducing clear water or other sealing fluid 45 underpressure at an intermediate point of the stuffing box where some of thepacking material is replaced by a so-called lantern or water seal ring16. Casing I I is provided at one end thereof with a tubular extensionwhich forms a suction passage l1 and which is adapted to be bolted orotherwise fastened to the suction piping (not shown) conducting thefluid stream to the pump. Access may be obtained to the suction passagethrough a hand hole provided with a cover I8 carrying a bafiie or guidevane i 9. The peripheral portion of casing forms a spiral dischargepassage 2| adapted to lead the fluid passing through the pump todischarge piping (not shown). The intermediate portion of casingpreferably comprises a pair of removable side plates 22, 23 held thereinby tongue and groove annular joints and shaped to conform to thestructure of the impeller with the least possible clearance. The suctionside plate 22 is provided with an inwardly projecting flange or bafile24 forming an inlet eye coaxial with runner l2.

The runner comprises a hub portion 26 of generally conical form rigidlyfastened to the end of shaft |3 in any suitable manner, and a pluralityof suitably shaped vanes. Each vane such as 2'. is preferably of spiralshape having an inlet edge 28 adjacent the eye of the pump, a dischargeedge 29 adjacent discharge passage 2| and afree outer edge 3| movableadjacent side plate 22 with a clearance space therebetween. Inlet edge28 joins hub 26 with outer edge 3| and thus intersects the entireincoming flow of fluid. Edge 28 comprises a convex portion 32 adjacenthub 26 and merging into a concave portion 33. The outer end of edge 28is provided with a stop 34 which may be made integral with the vane ormay be made as a separate piece. As illustrated in Figs. 1, 2 and 3,stop 34 may be shaped as an extension of the web of vane 2'! or, asillustrated in Figs. 4 and 5, the stop may be formed as a pair offlanges 35 extending from edge 28 along outer edge 3| and on oppositesides of vane 2! and having their trailing edges faired into the vane.It will be understood that other forms of stop may also be used, such asa stop forming a continuous flange extending along outer edge 3| on bothsides of vane 21 and around the end of edge 28. Fig. 3 shows the contourof edge 28 of the runner illustrated in Figs. 1 and 2 and a plurality ofcontour lines assumed to be drawn on the surface of the edge. Edgeportion 32 may be given any cross section facilitating the flow of fluidon both sides thereof and may be substantially semielliptical in crosssection with a small radius at the tip, but edge portion 33 istransversely rounded with a relatively large radius at least immediatelyadjacent stop as. The cross sections of edge portions 32 and 33 varyfrom point to point to insure a smooth transition between the two edgeportions.

During normal operation of the pump, runner I2 is rotated through shafti3 in the counterclockwise direction as viewed in Fig. 2, and therotating spiral vanes of the runner cause the fluid to enter the suctionopening formed in the passage l7 and to travel along the surfaces of theimpeller vanes and of the side plate 22 to be ultimately delivered tothe spiral discharge conduit 2| and to the discharge piping connectedtherewith. The fluid stream in passage I! is guided by guide vane I9which prevents the fluid from taking a whirling movement. Filamentarymaterial, such as string and rubber bands, carried by the fluid flow isgenerally of such density as to remain suspended in the fluid during thepassage thereof through the difierent parts of the pump. Some of thematerial may impinge on vane 52 which has a leading or inlet edgesloping in the direction of the fluid flow from the wall of casing Htoward the axis of passage ll. The vane thus releases filamentarymaterial impinging thereon toward the center of the fluid stream andtherefore at a point removed from the clearance space between the outeredges 3| of the runner vanes and side plate 22.

Some of the filamentary material also impinges on the inlet edge 28 ofeach runner vane in such manner as to lie across the edge and to be heldthereagainst by the flow of fluid. As a result of the convex form ofedge 32 and under the action of centrifugal force, filamentary materialcaught on the edge is gradually deflected outwardly along the edge, andif edge 28 were of uniform configuration, the material would be guidedto ultimately be released into the clearance between edge 3| and sideplate 22. To prevent the material from penetrating within the clearancespace, the inlet edge portion 33 is made concave to collect the materialimpinging on the edge portions 32 and 33. The material moving along theedge is thus stopped before reaching the clearance between the runnerand the casing, by means of stop 34. and remains on the rounded portionof the inlet edge just adjacent but within the stop. The materialresting on the rounded portion of the edge is in unstable equilibriumand is ultimately released into the fluid stream on one or on the otherside of the vane at a point removed from edge 3|.

It will be observed that flange 24 is disposed ahead of and adjacent thepath of stop 34. The flange thus cooperates with inlet edge 28 includingstop 34 in preventing filamentary material from entering the clearance(space between edge 3| and the adjacent portions of the casing bydeflecting the flow of fluid from the clearance and by preventingfilamentary material from impinging on the portion of edge 28 adjacentedge 3| and on stop 34. As filamentary material otherwise passingthrough the pump has no tendency to enter the clearances between therunner and the side plates, the continued undisturbed operation of thepump is thus insured.

In the embodiment illustrated in Figs. 6 and 7, the pump comprises acasing 36 of the branched tubular type defining an inlet passage for theflow of fluid and adapted to be connected with inlet piping (not shown).The runner 37 of the pump is of the axial or propeller type, arrangedwithin a sleeve 38 forming part of casing 36 or made as a separate pieceextending into the discharge pipe 39 of the pump. Runner 3'! is mountedon a suitable shaft 4| supported in a water lubricated bearing 42 andsealed by means of a stuffing box 43. Bearing 42 is mounted in a bearinghousing 44 extending into casing 36 and including stufiing box 43 and aplurality of guide vanes or baffles 46. Sleeve 38 is likewise providedwith a plurality of guide vanes 47. The guide vanes have their inlet orleading edges sloping in the direction of the fluid flow from the wallof the casing to release filamentary material impinging thereon, towardsthe center of the fluid stream. The runner is provided with a pluralityof vanes 48 mounted on the hub 49 fastened on shaft 4|. Each vane has aninlet edge and a discharge edge 52 joined by a free outer edge 53movable adjacent sleeve 38 with clearance therebetween. Inlet edge 5|comprises a portion 54 sloping in the direction of the fluid flow fromthe hub outward and on which material may impinge and thereafterprogress in direction of the fluid flow under the action of centrifugalforce. Each inlet edge is provided at the outer end with a stop 56 andthe portion 57 thereof intermediate portion 54 and stop 56 is madeconcave and rounded immediately within stop 56 to collect filamentarymaterial impinging on the inlet edge and to release the material intothefluid stream at'a point removed from the clearance between the outeredge and the adjacent portion of the casing. This action is assisted bya flange 58 extending inwardly from sleeve 38 and adjacent the path ofstop 56 to prevent filamentary material from impinging on the stop andto guide the material away from the clearance between the runner and thecasing. The action of the different parts of the pump in preventingclogging of the pump clearance is thus obtained in substantially thesame manner as in the embodiments illustrated in Figs. 1 to 4, and adetailed explanation thereof is accordingly omitted.

Although but a few embodiments of the present invention have beenillustrated and described, it will be apparent to those skilled in theart that various changes and modifications may be made therein withoutdeparting from the spirit of the invention or from the scope of theappended claims.

It is claimed and desired to secure by Letters Patent:

1. A rotary hydraulic machine adapted to conduct a fluid streamcontaining filamentary material comprising a casing and an open typerunner mounted for rotation within said casing, said runner comprising avane having an inlet edge and a free radially outer edge adjacent aportion of said casing with a peripheral clearance therebetween, saidinlet edge having a stop located adjacent its outer end and having aconcave portion adjacent the stop and being transversely roundedimmediately within said stop for collecting filamentary materialimpinging on said inlet edge and for releasing the collected materialinto the fluid stream at a point removed from the clearance between saidouter edge and the adjacent portion of said casing.

2. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a hub and a vanehaving an outer edge and an inlet edge joining said hub with said outeredge, said inlet edge having a portion adjacent said hub of convex formfor deflecting filamentary material impinging thereon and having aconcave portion forming a stop located adjacent its radially outer end,and being transversely rounded on different radii from said hub towardsaid stop for collecting the filamentary material impinging on said vaneand for releasing the collected material into the fluid stream at apoint removed from said outer edge.

3. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and an outer edge, the inlet edge being convex adjacent theinner end viewed axially and concave adjacent the outer end thereof forcollecting filamentary material impinging on the inlet edge and forreleasing the collected filamentary material into the fluid stream at apoint removed from the outer edge.

4. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and an outer edge, the inlet edge being convex adjacent theinner end viewed axially and concave adjacent the outer end thereof andbeing transversely rounded between the ends thereof for collectingfilamentary material impinging on the inlet edge and for releasing thecollected filamentary material into the fluid stream at a point removedfrom the outer edge.

5. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and an outer edge, the inlet edge being convex adjacent andbeing concave remote from the axis of said runner and being transverselyrounded on different radii between the ends thereof for collectingfilamentary material impinging on the inlet edge and for releasing thecollected filamentary material into the fluid stream at a point removedfrom the outer edge.

6. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and an outer edge, the inlet edge being convex adjacent theinner end viewed axially and concave adjacent the outer end thereof andbeing transversely rounded on different radii fairing into each otherbetween the ends thereof for collecting filamentary material impingingon the inlet edge and for releasing the collected filamentary materialinto the fluid stream at a point removed from the outer edge.

'7. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and an outer edge and a stop extending from the inlet edgeand having a concave portion adjacent the stop for collectingfilamentary material impinging on the inlet edge and for releasing thecollected filamentary material into the fluid stream at a point removedfrom the outer edge.

8. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and an outer edge, the inlet edge being convex adjacent theinner end and concave adjacent the outer end thereof and forming a stopextending from the outer end thereof for collecting filamentary materialimpinging on the inlet edge and for releasing the collected filamentarymaterial into the fluid stream at a point removed from the outer edge.

9. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and a free outer edge, the inlet edge being made convexadjacent the inner end and concave adjacent the outer end thereof toform a stop extending from the outer end thereof, the inlet edge of saidvane being transversely rounded between the ends thereof for collectingfilamentary material impinging on the inlet edge and for releasing thecollected fllamentary material into the fluid stream at a point removedfrom the outer edge.

10. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and a free outer edge, the inlet edge being made convexadjacent the inner end and concave adjacent the outer end thereofforming a stop extending from the outer end thereof, the inlet edge ofsaid vane being transversely rounded on different radii between the endsthereof for collecting filamentary material impinging on the inlet edgeand for releasing the collected filamentary material into the fluidstream at a point removed from the outer edge.

11. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and a free outer edge, the inlet edge being made convexadjacent the inner end and concave adjacent the outer end thereof andforming a stop extending from the outer end thereof, the inlet edge ofsaid vane being transversely rounded on different radii fairing intoeach other between the ends thereof for collecting filamentary materialimpinging on the inlet edge and for releasing the collected filamentarymaterial into the fluid stream at a point removed from the outer edge.

12. In a rotary hydraulic machine for conducting a fluid streamcontaining filamentary material, a runner comprising a vane having aninlet edge and a free outer edge, the inlet edge being made convexadjacent the inner end and. concave adjacent the outer end thereof andforming a stop extending from the outer end thereof, the inlet edge ofsaid vane being transversely rounded on a relatively small radius at theinner end and a relatively large radius at the outer end thereof forcollecting filamentary material impinging on the inlet edge and forreleasing the collected filamentary material into the fluid stream at apoint 10 remover from the outer edge.

FRANK R. FORREST.

